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Unless you’re a newbie, you’re most likely aware of my years of struggling with root knot nematodes. I would love to say that my newly discovered organic methods such as compost tea, wood chip mulch, and crab shell (chitin – pronounced kite-in) have eradicated my nemesis, but I can confidently announce that there’s progress! Since starting my SFG in 2013, I’ve been solarizing every summer.

Yesterday I discovered tomato plant roots all knotted up with nematodes. The good news is that by this time previous years I would have found RKN damage in all three of my SFG beds months ago! The other good news is that I’ve discovered that I now have an army of microbes fighting with me. To borrow a title of a great book: "Teaming with Microbes", I’m not alone in my fight anymore. In the coming months I’ll be watching to see how effective compost tea and crab shell chitin is in controlling RKN’s.

Yesterday after pulling out as many of the infected roots I could find, I worked 4 Tbsp of crab meal to each infected square, and drenched it with my 48 hour brew of CT. I may leave those squares empty for 4 weeks before replanting. By the end of May if I still have a problem I’ll solarize the bed.

One more thought, I've read from the beginning of my research that RKN's thrive in poor soil. Well, I don't think I had a good grasp of what rich soil was. The RKN's that I have aren't deterred by all the organic matter, which conflicts with all I've read. And when I read that they don't do well in rich soil, I thought, "I've been fertilizing... I have NPK..." Plus, I use plenty of organic matter...COMPOST... in my MM! My hope is that as I keep enriching my MM with CT, worm castings, chitin, wood chip mulch, kelp meal (which I'm making myself now), etc. that I'll eventually eradicate those suckers with the help of my army of microbes.

How do you make your own kelp meal. In CA, the seaweed is large, large stems, leaves and fans. I tried grinding it wet. Tried grinding it dried. Nothing worked.

Sanderson, are you using a blender or a food processor? I use the Ninja cup. Also, are you buying your kelp, or getting it from the beach? I buy my kelp from an Asian market. I rinse mine off in case there is salt residue. Here's the video that got me started with this.

Well, I think I found why the one tomato wasn't doing well. Digging to prep a quick set of bush beans. Pulled this out from the spot the celery was in before it got too hot. Not sure if these are from the celery or the tomato. Bad news I pulled some romaine that wasn't forming head due to heat and their roots showed the same bumps.

@No_Such_Reality wrote:Well, I think I found why the one tomato wasn't doing well. Digging to prep a quick set of bush beans. Pulled this out from the spot the celery was in before it got too hot. Not sure if these are from the celery or the tomato. Bad news I pulled some romaine that wasn't forming head due to heat and their roots showed the same bumps.

Looks all too familiar. I've had root knot on various lettuce plants, so not surprised about the romaine. It's never nice to find a RKN infection.

@No_Such_Reality wrote:Fortunately, or maybe unfortunately, RKN is an endemic problem in OC getting plenty of coverage and attention.

I think I may be planting marigolds this winter. http://www.ocregister.com/2015/06/10/plant-marigolds-to-stop-root-knot-nematodes/

I recommend French Marigolds. Some varieties of Marigolds will actually HOST some strains of RKNs, and I've seen it happen in my own garden. I was HORRIFIED! Then came across an article about it that a professor at the University of Florida sent me which explains this. I wrote about this...